Both bendouts lost fish, but the top one is pretty extreme, eh?
Never got to see either fugitive, but reviewing my catch log, the dozen or so I caught on the 1/16 #4 Sickle Boolies topped out at 17", so guessing it took bigger to bend out. I remember the big bender - it felt exceptionally sizeable.
And yeah, #8 & #6 Sickle wire diameters seem adequate for the hook sizes, but standard #4 & 2 already seem a bit thin IMO, so off grade thinner would indeed invite failure, especially if the temper was on the soft side.